William s



(No Model.)

W. S. ANDREWS.

SAFETY CATCH.

Patented Aug. 31, 1886.

INVENTDB:

UNITED STATES PATENT OFFICE.

WILLIAM S. ANDRE\VS, OF NEW YORK, N. Y.

SAFETY-CATCH.

SPECIFICATION forming part of Letters Patent No. 348,371, dated August31, 1886.

Application filed Novrmbcr 20, 1884.

To aZZ whom, it may concern.-

Be it known that 1, WILLIAM S. ANDREWS, of New York city, in the countyand State of New York, have invented a new and useful Improvement inSafety-Catches, of which the following is a specification.

The object I have in view is to produce a simple and efficient form offusible safety-catch for electrical circuits employing heavycurrentssuch as the circuits of electric-light plants or those ofsystems of electrical distribution for light, power, and other purposes.

My device is more especially designed for use upon conductors run uponpolessuch as are employed for the feeder and main circuits of the Edisonthree-wire or compensating system, as constructed for villages-whichconductors are exposed to the weather; but the features of the inventionare also applicable to safety-catches generally without regard to theirparticular location.

The invention will be understood by reference to the accompanyingdrawings, in which Figure 1 is a plan view of a single-part safetycatch;Fig. 2, a central section through the same; Fig. 3, aseparate plan viewof the safetycatch proper; Figs. 4 and 5, plan views of a two-partsafety-catch ona smaller scale; Figs. 6 and '7, plan views of athree-part and a fourpart safety-catch, respectively; Figs. 8 and 9, aplan view and side elevation of the separate radial part of which themultiple catch is made up; Figs. ll) and 11., a plan view and side elevation of the center piece, for two and three part catches, and Fig. 12an elevation of the center piece for the catch having four or moreradial parts.

Like letters denote corresponding parts in all the figures.

The preferred form of my safety'catch A, Fig. 3, considered apart fromits supports, is a number (two or more) of wires, a, of lead or othereasily-fused metal, secured by soldering, fusing, or otherwise to commonend plates, Z) I), of harder metal, such as copper. These end plates areslotted, as shown, for securing the safety-catch in position.

The advantage of using a number of fusible wires secured to common endplates over a solid strip of lead is that the conducting capacity of thecatch can be more accurately determined. The conductivity of one strandof Serial No. 148,378. (No model.)

the fusible wire and its fusing-point with relation to the current beingdetermined, a safetycatch composed of a number of lengths of such wirewill be known to have a definite fusingpoint with relation to thecurrent, since the radiating surface of the safety-catchincreasesdirectly as its conductivity; but with safetycatches of different sizes,each composed of a single piece offusible metal,the relativefusingpoints of the several catches cannot be determined by theirrelative resistances, since the radiating surface does not bear the samerelation to conductivity in any two of the catches.

The simplest form of support for my safetycatch, Figs. 1 and 2, iscomposed of two metal frames, B 0, connected byablock, D, of stonewareor other suitable insulation. The block D is cemented at its ends in themetal frames, or otherwise secured thereto. are secured in the frames onone side, and receive nuts and washers for securing the end platesof thecatch A. The metal frames B O are provided with sleeves d d,casttherewith, which receive the ends of the wires forming the line in whichthe safety-catch is interpolated, such sleeves having set-screws d forse curing the wires within them. This construction is an exceedinglysimple and effective one, the parts being weather-proof,strong, anddurable.

The single safety-catch is intended for use in a line at a point beyondwhich the conductors are reduced in size. In a three-wire system thismay frequently occur. I interpolate one of my catches at such point ineach of the two outer eonductors-thc positive and negative-the centralor compensating wire not being protected by safety-catches, althoughitmay be. For a nmltiple-part safety-catch I mount the safety-catches Aupon metal frames 13 0, connected by stoneware blocks D. The outer metalframe, 0, has a wire-connecting sleeve, d,while the inner frame, 13, isprovided with aperforated flat lip, e. For a two 'or three part catch Iprovide a metal center piece, E, having a perforated lip, f, and ahorizontal wire-connecting sleeve, 9. By means of a center bolt, h, thetwo or three safety-catch parts are secured to the center piece.

For a catch having four or more parts the metal center piece, F, hasaycrtical wire-connecting sleeve, 17, so that the safety-catch partsStud-screws cc" ductors, so that the strain will be taken lengthwise ofthe stoneware blocks. It is evident that this form of construction couldalso be applied to a single-part safety-catch, one part being secured tothe center piece,instead of two or more. I

The supporting-frames of my catches are covered with a suitableweather-proof paint or material, except upon surfaces where electricalconnections are made,where they areleft' bare, and where, if desired,they may be plated with gold or other metal not easily oxidized.

My safety-catches when used upon air-lines are designed to be supportedby the wires themselves, the connecting-sleeves and setscrews being anefiicient construction for this purpose; but they may be secured to thepoles.

in any suitable manner.

What I claim is r 1. The combination, with the metal frames or socketsand connecting-block of insulation enterlng such frames or sockets andsecured therein, said frame or brackets surrounding the ends of theconnecting-block, of the safety-catch secured to such metal frames,substantially asset forth. 7

2. The combination, with the metal frames or sockets andconnecting-block of earthenware entering such frames or sockets andsecured therein, said frames or sockets surrounding the ends of theconnecting-block, of the safety-catch secured to such metal frames,substantially as set forth. i

3. A multiple-part safety-catch having, in combination, a center piece,two or more safety-catches radiating therefrom, and conneoting devicesfor connecting wires to such center piece and to the outer ends of thesafety-catches, substantially as set forth.

4. In a multiple-part safety-catch, the C011!- bination of a metalcenter piece with two or more safety-catches mounted upon separatesupports and removably connected to such center piece, substantially asset forth.

5. The combination of an insulating-block, metal frames secured to theends of the block, a fusible safety-catch connecting such metal frames,a wire-connecting sleeve on one of such frames, and a perforated lug onthe other frame, substantially as and for the purpose set forth.

This specification signed and witnessed this 4th day of November, 1884 pWILLIAM S. ANDREWVS. Witnesses:

p F. H. WHITING,

.G. W. LEWIs.

